code: def test_orderbycreatedattimestamp_partitionkey() -> None:
      random_datetime = DateTime.now()
  
      assert OrderByCreatedAtTimeStampPartitionKey.key == "created_at"
      assert OrderByCreatedAtTimeStampPartitionKey.type_ == DateTime
  
      result = OrderByCreatedAtTimeStampPartitionKey.with_obj(
          random_datetime
      )
  
      assert result.type_ == DateTime
      assert result.key == "created_at"
      assert result.value == random_datetime
  
imports: import pytest
  from pytest import MonkeyPatch
  from result import Err
  from syft.node.credentials import SyftSigningKey
  from syft.node.credentials import SyftVerifyKey
  from syft.service.notification.notification_stash import OrderByCreatedAtTimeStampPartitionKey
  from syft.service.notification.notification_stash import FromUserVerifyKeyPartitionKey
  from syft.service.notification.notification_stash import NotificationStash
  from syft.service.notification.notification_stash import StatusPartitionKey
  from syft.service.notification.notification_stash import ToUserVerifyKeyPartitionKey
  from syft.service.notification.notifications import Notification
  from syft.service.notification.notifications import NotificationExpiryStatus
  from syft.service.notification.notifications import NotificationStatus
  from syft.types.datetime import DateTime
  from syft.types.uid import UID
label_desc: Use image node_id 5 for calling a global function with example usage: test_orderbycreatedattimestamp_partitionkey() without return types